A conventional push-button switch is known from published Japanese Examined Utility Model No. 63-82327. In this connection, the push-button switch disclosed therein includes a switch body which has a front attachment plate formed of an electrically insulating material and a central hollow portion in which the shaft of the operation button may be slidably inserted. The operation button includes a primary fixed contact member and is inserted into one end of the switch body. The operation button is positionally restrained within the switch body by means of a pair of contact member insertion holes formed on the switch body's exterior. A secondary fixed contact is inserted into an opposite end of the switch body. The operation button protrudes beyond the switch and is resiliently maintained within the switch body by a movable contact member which is fixed onto the end of the operation button and includes a pair of resilient conducting pieces. The resilient conducting pieces are disposed so that contact is made at the contact point between the primary and secondary fixed contact members.
One problem associated with conventional push-button switches of the structure as described above is that the operation button is not positionally restrained during assembly, thereby making the assembly operation more tedious and/or difficult. According to the present invention, however, a push-button switch is provided which is relatively easily assembled as compared to typical push-button switches of the prior art.
In this connection, the push-button switches of the present invention are provided with a housing having opposed pairs of side walls defining an interior space, and an opposed pair of fixed contact members. A push-button assembly is received within the interior space of the housing for reciprocal movements between extended and retracted positions. The push-button assembly includes a pair of opposed side windows having lower extents established by a bridge wall. A spring exerts a bias force to move the push-button assembly into its extended position.
A generally inverted V-shaped slide contact member is movable with the push-button assembly between its extended and retracted positions, and includes a pair of resilient legs each having an outwardly curved contact region The contact regions serve to contact the pair of fixed contact members when the push-button assembly is moved into one of its extended and retracted positions whereby an electrical circuit is made, and breaks contact with at least one of the fixed pair of contacts when the push-button assembly is moved into the other of its extended and retracted positions, whereby an electrical circuit is broken.
The slide contact member further includes terminal end flanges extending from the curved contact regions, the terminal end flanges being positioned so as to contact a respective bridge wall of an associated side window and thereby limit the extent of outward resilient displacement of the legs of the slide contact member. As a result of this limited outward displacement, the slide contact member may be temporarily (but securely) positioned within the push-button assembly so as to facilitate automated coupling of the push-button assembly and the housing during fabrication.
Further aspects and advantages of this invention will become more clear after careful consideration is given to the detailed description of the preferred exemplary embodiments thereof which follow.